Glyphis garricki
Glyphis garricki (''Northern river shark)' Kingdom: '''Animalia Phylum: Chordata Class: Chondrichthyes Order: Carcharhiniformes Family: Carcharhinidae Genus: Glyphis Species: Glyphis garricki Environment: milieu, climate zone, depth range, distribution range: Marine; brackish; pelagic-oceanic; depth range ? - 11 m. Tropical. Distribution: Indo-West Pacific: Australia (salinities 6-26 and 32-36.6) and New Guinea. Size, weight, age: Max. length: 1.45 m (male), 2.51 m (female) Short description: Like other members of its genus, the northern river shark has a stocky body with a high back. The head is wide and flattened, with a broadly rounded snout and minute eyes equipped with nictitating membranes. Each nostril is divided into a very large incurrent opening and a small excurrent opening by a triangular skin flap. The sizable mouth is broadly arched, with short furrows at the corners. Thirty-one to 34 tooth rows are in the upper jaw and 30–35 tooth rows are in the lower jaw; the upper teeth are upright and triangular with serrated edges, while the lower teeth are narrower and straight to slightly curved. In the largest individuals, the first few lower teeth from the jaw median are spear-shaped with serrations near the tip. The pectoral fins are large and broad, with gently backward-curving margins and pointed tips. The pelvic fins are triangular with nearly straight trailing margins. The first dorsal fin is long-based and triangular, with the apex almost forming a right angle; the second dorsal fin is some two-thirds as high as the first. The origin of the first dorsal fin lies over the pectoral fin insertions, while that of second dorsal fin lies over the pelvic fin rear tips. No ridge exists between the dorsal fins. The anal fin is smaller than the second dorsal fin and has a strong notch in the rear margin. The caudal fin has a strong lower lobe and a long, narrow upper lobe with a ventral notch near the tip. The dermal denticles are small, oval, and overlapping, bearing three horizontal ridges leading to marginal teeth. This shark is steel-gray above and white below; the color transition is sharp, located well below the eye, and becomes jagged on the sides of the trunk. The anal and caudal fins become dusky or black towards the trailing margins and tips. The maximum known length is 2.5 m (8.2 ft). This species differs from the speartooth shark (G. glyphis) in several morphological and meristic characters, including having fewer vertebrae (137–151 versus 213–222) and a lower, jagged gray-white color boundary. Biology: With its slender teeth, small eyes, and high density of ampullae of Lorenzini, the northern river shark seems to be adapted for hunting fish in conditions of poor visibility. In Doctors Creek, sharks may move to and from favored feeding areas with the tide. Like other requiem sharks, this species is viviparous, with the developing embryos forming a placental connection to their mother after exhausting their supply of yolk. Females give birth around October, before the start of the wet season, on possibly a biennial cycle. One female examined contained nine fetuses. The young are born at under 67 cm (26 in) long; males mature between lengths of 1.2 and 1.4 m (3.9 and 4.6 ft), while females mature between lengths of 1.4 and 1.7 m (4.6 and 5.6 ft). Life cycle and mating behavior: ?''' ''Main reference:'' '''Compagno, L.J.V., W.T. White and P.R. Last, 2008. Glyphis garricki sp. nov., a new species of river shark (Carcharhiniformes: Carcharhinidae) from northern Australia and Papua New Guinea, with a redescription of Glyphis glyphis (Müller & Henle, 1839). In Last, P.R., White, W.T. & Pogonoski, J.J. (eds.): Descriptions of New Australian Chondrichthyans. CSIRO Marine and Atmospheric Research Paper no. 22. IUCN Red List Status: CRITICALLY ENDANGERED (''CR)' '''CITES: Not Evaluated CMS: Not Evaluated Threat to humans: Harmless Human uses: FAO. Category:Carcharhinidae, Sharks